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Microwave Enthrakometric Labs-On-A-Chip and On-Chip Enthrakometric Catalymetry: From Non-Conventional Chemotronics Towards Microwave-Assisted Chemosensors. CHEMOSENSORS 2019. [DOI: 10.3390/chemosensors7040048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A unique chemical analytical approach is proposed based on the integration of chemical radiophysics with electrochemistry at the catalytically-active surface. This approach includes integration of: radiofrequency modulation polarography with platinum electrodes, applied as film enthrakometers for microwave measurements; microwave thermal analysis performed on enthrakometers as bolometric sensors; catalytic measurements, including registration of chemical self-oscillations on the surface of a platinum enthrakometer as the chemosensor; measurements on the Pt chemosensor implemented as an electrochemical chip with the enthrakometer walls acting as the chip walls; chemotron measurements and data processing in real time on the surface of the enthrakometric chip; microwave electron paramagnetic resonance (EPR) measurements using an enthrakometer both as a substrate and a microwave power meter; microwave acceleration of chemical reactions and microwave catalysis оn the Pt surface; chemical generation of radio- and microwaves, and microwave spin catalysis; and magnetic isotope measurements on the enthrakometric chip. The above approach allows one to perform multiparametric physical and electrochemical sensing on a single active enthrakometric surface, combining the properties of the selective electrochemical sensor and an additive physical detector.
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Jang H, Kang IS, Kim J, Kim J, Cha YJ, Yoon DK, Lee W. Nanofluidic chip for liquid TEM cell fabricated by parylene and silicon nitride direct bonding. NANOTECHNOLOGY 2017; 28:375301. [PMID: 28737164 DOI: 10.1088/1361-6528/aa8196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Despite the importance of nanofluidic transmission electron microscope (TEM) chips, a simple fabrication method has yet to be developed due to the difficulty of wafer bonding techniques using a nanoscale thick bonding layer. We present a simple and robust wafer scale bonding technique using parylene as a bonding layer. A nanoscale thick parylene layer was deposited on a silicon nitride (SiN) wafer and patterned to construct nanofluidic channels. The patterned parylene layer was directly bonded to another SiN wafer by thermal surface activation and bonding, with a bonding strength of ∼3 MPa. Fourier transform infrared spectroscopy showed that carbon-oxygen bonds were generated by thermal activation. We demonstrated TEM imaging of gold nanoparticles suspended in liquid using the fabricated nanofluidic chip.
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Affiliation(s)
- Heejun Jang
- Graduate School of Nanoscience and Technology, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea. KAIST Institute for NanoCentury, KAIST, Daejeon 34141, Republic of Korea
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Turbulence in microfluidics: Cleanroom-free, fast, solventless, and bondless fabrication and application in high throughput liquid-liquid extraction. Anal Chim Acta 2016; 940:73-83. [DOI: 10.1016/j.aca.2016.08.052] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 08/27/2016] [Accepted: 08/29/2016] [Indexed: 11/13/2022]
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Continuous quantification of HER2 expression by microfluidic precision immunofluorescence estimates HER2 gene amplification in breast cancer. Sci Rep 2016; 6:20277. [PMID: 26856369 PMCID: PMC4746572 DOI: 10.1038/srep20277] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 12/23/2015] [Indexed: 01/05/2023] Open
Abstract
Chromogenic immunohistochemistry (IHC) is omnipresent in cancer diagnosis, but has also been criticized for its technical limit in quantifying the level of protein expression on tissue sections, thus potentially masking clinically relevant data. Shifting from qualitative to quantitative, immunofluorescence (IF) has recently gained attention, yet the question of how precisely IF can quantify antigen expression remains unanswered, regarding in particular its technical limitations and applicability to multiple markers. Here we introduce microfluidic precision IF, which accurately quantifies the target expression level in a continuous scale based on microfluidic IF staining of standard tissue sections and low-complexity automated image analysis. We show that the level of HER2 protein expression, as continuously quantified using microfluidic precision IF in 25 breast cancer cases, including several cases with equivocal IHC result, can predict the number of HER2 gene copies as assessed by fluorescence in situ hybridization (FISH). Finally, we demonstrate that the working principle of this technology is not restricted to HER2 but can be extended to other biomarkers. We anticipate that our method has the potential of providing automated, fast and high-quality quantitative in situ biomarker data using low-cost immunofluorescence assays, as increasingly required in the era of individually tailored cancer therapy.
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Fink JK. Poly(<mml:math altimg="si22.gif" overflow="scroll" xmlns:xocs="http://www.elsevier.com/xml/xocs/dtd" xmlns="http://www.elsevier.com/xml/bk/dtd" xmlns:bk="http://www.elsevier.com/xml/bk/dtd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:tb="http://www.elsevier.com/xml/common/table/dtd" xmlns:sb="http://www.elsevier.com/xml/common/struct-bib/dtd" xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:cals="http://www.elsevier.com/xml/common/cals/dtd"><mml:mrow><mml:mi mathvariant="bold-italic">p</mml:mi></mml:mrow></mml:math>-xylylene)s. HIGH PERFORM POLYM 2014. [DOI: 10.1016/b978-0-323-31222-6.00002-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Dupouy DG, Ciftlik AT, Teixidor J, Gijs MAM. Programming and use of Parylene C fluorescence as a quantitative on-chip reference. RSC Adv 2014. [DOI: 10.1039/c4ra08982k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A large number of lab-on-a-chip applications use fluorescence for quantifying biological entities.
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Affiliation(s)
- Diego G. Dupouy
- Laboratory of Microsystems 2
- École Polytechnique Fédérale de Lausanne
- CH-1015 Lausanne, Switzerland
| | - Ata Tuna Ciftlik
- Laboratory of Microsystems 2
- École Polytechnique Fédérale de Lausanne
- CH-1015 Lausanne, Switzerland
| | - Joan Teixidor
- Laboratory of Microsystems 2
- École Polytechnique Fédérale de Lausanne
- CH-1015 Lausanne, Switzerland
| | - Martin A. M. Gijs
- Laboratory of Microsystems 2
- École Polytechnique Fédérale de Lausanne
- CH-1015 Lausanne, Switzerland
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7
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Madadi H, Mohammadi M, Casals-Terré J, López RC. A novel fabrication technique to minimize poly(dimethylsiloxane)-microchannels deformation under high-pressure operation. Electrophoresis 2013; 34:3126-32. [PMID: 24114728 DOI: 10.1002/elps.201300340] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2013] [Revised: 08/21/2013] [Accepted: 09/02/2013] [Indexed: 11/06/2022]
Abstract
PDMS is one of the most common materials used for the flow delivery in the microfluidics chips, since it is clear, inert, nontoxic, and nonflammable. Its inexpensiveness, straightforward fabrication, and biological compatibility have made it a favorite material in the exploratory stages of the bio-microfluidic devices. If small footprint assays want to be performed while keeping the throughput, high pressure-rated channels should be used, but PDMS flexibility causes an important issue since it can generate a large variation of microchannel geometry. In this work, a novel fabrication technique based on the prevention of PDMS deformation is developed. A photo-sensible thiolene resin (Norland Optical Adhesive 63, NOA 63) is used to create a rigid coating layer over the stiff PDMS micropillar array, which significantly reduces the pressure-induced shape changes. This method uses the exact same soft lithography manufacturing equipment. The verification of the presented technique was investigated experimentally and numerically and the manufactured samples showed a deformation 70% lower than PDMS conventional samples.
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Affiliation(s)
- Hojjat Madadi
- Technical University of Catalonia, Mechanical Engineering Department, Terrassa, Spain
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Huang Y, Mason AJ. Lab-on-CMOS integration of microfluidics and electrochemical sensors. LAB ON A CHIP 2013; 13:3929-34. [PMID: 23939616 PMCID: PMC3793889 DOI: 10.1039/c3lc50437a] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
This paper introduces a CMOS-microfluidics integration scheme for electrochemical microsystems. A CMOS chip was embedded into a micro-machined silicon carrier. By leveling the CMOS chip and carrier surface to within 100 nm, an expanded obstacle-free surface suitable for photolithography was achieved. Thin film metal planar interconnects were microfabricated to bridge CMOS pads to the perimeter of the carrier, leaving a flat and smooth surface for integrating microfluidic structures. A model device containing SU-8 microfluidic mixers and detection channels crossing over microelectrodes on a CMOS integrated circuit was constructed using the chip-carrier assembly scheme. Functional integrity of microfluidic structures and on-CMOS electrodes was verified by a simultaneous sample dilution and electrochemical detection experiment within multi-channel microfluidics. This lab-on-CMOS integration process is capable of high packing density, is suitable for wafer-level batch production, and opens new opportunities to combine the performance benefits of on-CMOS sensors with lab-on-chip platforms.
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Affiliation(s)
- Yue Huang
- Electrical and Computer Engineering Department, Michigan State University, East Lansing, MI 48824, USA.
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Ciftlik AT, Ettori M, Gijs MAM. High throughput-per-footprint inertial focusing. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2013; 9:2764-73, 2828. [PMID: 23420756 DOI: 10.1002/smll.201201770] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Revised: 11/19/2012] [Indexed: 05/22/2023]
Abstract
Matching the scale of microfluidic flow systems with that of microelectronic chips for realizing monolithically integrated systems still needs to be accomplished. However, this is appealing only if such re-scaling does not compromise the fluidic throughput. This is related to the fact that the cost of microelectronic circuits primarily depends on the layout footprint, while the performance of many microfluidic systems, like flow cytometers, is measured by the throughput. The simple operation of inertial particle focusing makes it a promising technique for use in such integrated flow cytometer applications, however, microfluidic footprints demonstrated so far preclude monolithic integration. Here, the scaling limits of throughput-per-footprint (TPFP) in using inertial focusing are explored by studying the interplay between theory, the effect of channel Reynolds numbers up to 1500 on focusing, the entry length for the laminar flow to develop, and pressure resistance of the microchannels. Inertial particle focusing is demonstrated with a TPFP up to 0.3 L/(min cm²) in high aspect-ratio rectangular microfluidic channels that are readily fabricated with a post-CMOS integratable process, suggesting at least a 100-fold improvement compared to previously demonstrated techniques. Not only can this be an enabling technology for realizing cost-effective monolithically integrated flow cytometry devices, but the methodology represented here can also open perspectives for miniaturization of many biomedical microfluidic applications requiring monolithic integration with microelectronics without compromising the throughput.
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Affiliation(s)
- Ata Tuna Ciftlik
- Laboratory of Microsystems 2, Ecole Polytechnqiue Federale de Lausanne-EPFL, CH-1015 Lausanne, Switzerland
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Ciftlik AT, Dupouy DG, Gijs MAM. Programmable parylene-C bonding layer fluorescence for storing information on microfluidic chips. LAB ON A CHIP 2013; 13:1482-1488. [PMID: 23426060 DOI: 10.1039/c3lc41280f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We demonstrate data storage on glass/silicon microfluidic devices fabricated using parylene-C as a bonding layer. In particular, we report intermediate parylene-C bonding layer fluorescence (iPBLF) and its use as an on-chip medium for data storage by dynamic programming of iPBLF intensity, using alternating exposure of parylene-C to UV and Green light. This technique allows data on the microfluidic chip to be read, written and erased by a common fluorescent microscope. Until now, no studies have focused on storing data like expiry date, protocol or operational parameters on a chip. However, this can be useful to overcome certain automation challenges in industrial applications for which communication of information is required, like needed during operation of remote microfluidic platforms. Finally, we also demonstrate the application of iPBLF for detecting channel dimensions and positions, and for marking on-chip zones of particular interest.
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Affiliation(s)
- Ata Tuna Ciftlik
- Laboratory of Microsystems 2, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
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Microfluidic processor allows rapid HER2 immunohistochemistry of breast carcinomas and significantly reduces ambiguous (2+) read-outs. Proc Natl Acad Sci U S A 2013; 110:5363-8. [PMID: 23479638 DOI: 10.1073/pnas.1211273110] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Biomarker analysis is playing an essential role in cancer diagnosis, prognosis, and prediction. Quantitative assessment of immunohistochemical biomarker expression on tumor tissues is of clinical relevance when deciding targeted treatments for cancer patients. Here, we report a microfluidic tissue processor that permits accurate quantification of the expression of biomarkers on tissue sections, enabled by the ultra-rapid and uniform fluidic exchange of the device. An important clinical biomarker for invasive breast cancer is human epidermal growth factor receptor 2 [(HER2), also known as neu], a transmembrane tyrosine kinase that connotes adverse prognostic information for the patients concerned and serves as a target for personalized treatment using the humanized antibody trastuzumab. Unfortunately, when using state-of-the-art methods, the intensity of an immunohistochemical signal is not proportional to the extent of biomarker expression, causing ambiguous outcomes. Using our device, we performed tests on 76 invasive breast carcinoma cases expressing various levels of HER2. We eliminated more than 90% of the ambiguous results (n = 27), correctly assigning cases to the amplification status as assessed by in situ hybridization controls, whereas the concordance for HER2-negative (n = 31) and -positive (n = 18) cases was 100%. Our results demonstrate the clinical potential of microfluidics for accurate biomarker expression analysis. We anticipate our technique will be a diagnostic tool that will provide better and more reliable data, onto which future treatment regimes can be based.
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Raos BJ, Unsworth CP, Costa JL, Rohde CA, Doyle CS, Bunting AS, Delivopoulos E, Murray AF, Dickinson ME, Simpson MC, Graham ES. Infra-red laser ablative micromachining of parylene-C on SiO2 substrates for rapid prototyping, high yield, human neuronal cell patterning. Biofabrication 2013; 5:025006. [PMID: 23466346 DOI: 10.1088/1758-5082/5/2/025006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Cell patterning commonly employs photolithographic methods for the micro fabrication of structures on silicon chips. These require expensive photo-mask development and complex photolithographic processing. Laser based patterning of cells has been studied in vitro and laser ablation of polymers is an active area of research promising high aspect ratios. This paper disseminates how 800 nm femtosecond infrared (IR) laser radiation can be successfully used to perform laser ablative micromachining of parylene-C on SiO2 substrates for the patterning of human hNT astrocytes (derived from the human teratocarcinoma cell line (hNT)) whilst 248 nm nanosecond ultra-violet laser radiation produces photo-oxidization of the parylene-C and destroys cell patterning. In this work, we report the laser ablation methods used and the ablation characteristics of parylene-C for IR pulse fluences. Results follow that support the validity of using IR laser ablative micromachining for patterning human hNT astrocytes cells. We disseminate the variation in yield of patterned hNT astrocytes on parylene-C with laser pulse spacing, pulse number, pulse fluence and parylene-C strip width. The findings demonstrate how laser ablative micromachining of parylene-C on SiO2 substrates can offer an accessible alternative for rapid prototyping, high yield cell patterning with broad application to multi-electrode arrays, cellular micro-arrays and microfluidics.
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Affiliation(s)
- B J Raos
- Department of Engineering Science, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
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